U.S. patent application number 11/309411 was filed with the patent office on 2007-04-26 for printed circuit board.
This patent application is currently assigned to HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to Ya-Ling Huang.
Application Number | 20070089903 11/309411 |
Document ID | / |
Family ID | 37984287 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070089903 |
Kind Code |
A1 |
Huang; Ya-Ling |
April 26, 2007 |
PRINTED CIRCUIT BOARD
Abstract
A printed circuit board includes a reference layer, a through
hole defined in the reference layer, and a plurality of insulating
areas are defined in the reference layer around the through hole.
The copper around the through hole is separated by the insulating
areas and forms a plurality of copper strips. The metal surface
area around the through hole available for heat dissipation is
reduced to slow down heat distribution. Defect formation is thus
reduced when the PCB is in a reflow process.
Inventors: |
Huang; Ya-Ling; (Shenzhen,
CN) |
Correspondence
Address: |
PCE INDUSTRY, INC.;ATT. CHENG-JU CHIANG JEFFREY T. KNAPP
458 E. LAMBERT ROAD
FULLERTON
CA
92835
US
|
Assignee: |
HON HAI PRECISION INDUSTRY CO.,
LTD.
Tu-Cheng
TW
|
Family ID: |
37984287 |
Appl. No.: |
11/309411 |
Filed: |
August 4, 2006 |
Current U.S.
Class: |
174/262 |
Current CPC
Class: |
H05K 3/3447 20130101;
H05K 3/429 20130101; H05K 2201/062 20130101; H05K 1/116 20130101;
H05K 2201/093 20130101; H05K 2201/09854 20130101; H05K 2201/0969
20130101 |
Class at
Publication: |
174/262 |
International
Class: |
H01R 12/04 20060101
H01R012/04; H05K 1/11 20060101 H05K001/11 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 24, 2005 |
CN |
200510100596.3 |
Claims
1. A printed circuit board (PCB) comprising: a reference layer; a
through hole for a lead of a component inserting therethrough
defined in the reference layer; and a plurality of insulating areas
defined in the reference layer around the through hole.
2. The PCB as claimed in claim 1, wherein the reference layer is a
solid copper layer.
3. The PCB as claimed in claim 2, wherein copper around the though
hole is separated by the plurality of insulating areas and forms a
plurality of copper strips.
4. The PCB as claimed in claim 3, wherein a width of each of the
copper strips is approximately 14 mils.
5. The PCB as claimed in claim 1, wherein a width of each of the
insulating areas is approximately 15 mils.
6. The PCB as claimed in claim 1, wherein the through hole has an
ellipse shape.
7. A method for making a printed circuit board (PCB) comprising
steps of: providng a reference layer with a through hole for a lead
of a component inserting therein; and etching a plurality of
insulating areas on the reference layer around the through hole for
a reduced area of heat dissipation.
8. The method as claimed in claim 7, wherein the reference layer is
a solid copper layer.
9. The method as claimed in claim 8, wherein copper around the
though hole is separated by the plurality of insulating areas and
forms a plurality of copper strips.
10. The PCB as claimed in claim 7, wherein the through hole has an
ellipse shape.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a printed circuit
board.
DESCRIPTION OF RELATED ART
[0002] Multilayer printed circuit boards (PCBs) are commonly used
in electronic devices to connect electronic components such as
integrated circuits to one another. A typical multilayer PCB
includes many layers of copper, with each layer of copper separated
by a dielectric material. Generally, several of the copper layers
are used to provide a reference voltage plane or ground plane.
[0003] Referring to FIG. 2, a reference plane of a printed circuit
board is provided. The printed circuit board 40 includes a
reference layer 41, and a through hole 34. A component is mounted
on the PCB 40 by inserting a lead through the through hole 34 in
the PCB 40 and then soldering the lead in place on the opposite
side of the PCB 40 during a reflow process. The lead of the
component is electrically connected to the reference plane. The
reference plane of the printed circuit board distributes heat
quickly due to a large surface area of copper. However, rapid heat
dissipation leads to defect formation in the soldering process.
[0004] It is therefore apparent that a need exits to provide a PCB
that can reduce defect formation when the PCB is in the reflow
process.
SUMMARY OF THE INVENTION
[0005] An exemplary printed circuit board includes a reference
layer, a through hole defined in the reference layer, and a
plurality of insulating areas are defined in the reference layer
around the through hole. The copper around the through hole is
separated by the insulating areas and forms a plurality of copper
strips. The metal area around the through hole available for heat
dissipation is reduced to slow down heat distribution. Thus, defect
formation is reduced when the PCB is in the reflow process.
[0006] Other advantages and novel features will become more
apparent from the following detailed description when taken in
conjunction with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a plan view of a reference plane of a printed
circuit board (PCB) in accordance with a preferred embodiment of
the preset invention; and
[0008] FIGS. 2 is a plan view of a reference plane of a
conventional PCB with a through hole defined therein.
DETAILED DESCRIPTION OF THE INVENTION
[0009] Referring to FIG. 1, a reference plane of a printed circuit
board (PCB) according to a preferred embodiment of the present
invention is provided. The PCB 50 includes a reference layer 51, a
through hole 52, and a plurality of etched insulating areas 53
surrounding the through hole 52. The through hole 52 is generally
ellipse shaped. The reference plane 51 is a solid copper layer. The
copper around the through hole 52 is separated by the insulating
areas 53 and forms a plurality of copper strips. The reference
layer 51 is electrically connected to the components inserted in
the through hole 52 by the copper strips. Preferably, a width of
the strips is approximately 14 mils, and a width of the insulating
areas is approximately 15 mils.
[0010] In this embodiment the metal area around the through hole 52
available for heat dissipation is much smaller than on conventional
PCBs, to slow down heat distribution. Defect formation is thus
reduced when the PCB is in a reflow process.
[0011] It is believed that the present invention and its advantages
will be understood from the foregoing description, and it will be
apparent that various changes may be made thereto without departing
from the spirit and scope of the invention or sacrificing all of
its material advantages, the examples hereinbefore described merely
being preferred or exemplary embodiments of the invention.
* * * * *